diff options
5 files changed, 298 insertions, 2 deletions
diff --git a/lldb/lit/SymbolFile/Breakpad/Inputs/stack-cfi-parsing.syms b/lldb/lit/SymbolFile/Breakpad/Inputs/stack-cfi-parsing.syms new file mode 100644 index 00000000000..1ebecb48022 --- /dev/null +++ b/lldb/lit/SymbolFile/Breakpad/Inputs/stack-cfi-parsing.syms @@ -0,0 +1,20 @@ +MODULE Linux x86_64 E5894855C35DCCCCCCCCCCCCCCCCCCCC0 linux.out +INFO CODE_ID E35C283BC327C28762DB788BF5A4078BE2351448 +FUNC 0 2 0 func0 +FUNC 2 1 0 func2 +FUNC 3 1 0 func3 +FUNC 4 1 0 func4 +FUNC 5 1 0 func5 +FUNC 6 1 0 func6 +FUNC 7 2 0 func7 +FUNC 9 1 0 func9 +STACK CFI INIT 0 2 .cfa: $rsp .ra: .cfa $rbp: $rsp +STACK CFI 1 $rbp: $rax $rbx: $rcx +STACK CFI INIT 2 1 $r47: $r42 +STACK CFI INIT 3 1 $rbp: +STACK CFI INIT 4 1 $rbp +STACK CFI INIT 5 1 $rbp: $rbx $rsp: +STACK CFI INIT 6 1 $rbp: $rsp: +STACK CFI INIT 7 1 .cfa: $rsp +STACK CFI bogus +STACK CFI INIT 9 1 .cfa: $rbp .ra: $rax diff --git a/lldb/lit/SymbolFile/Breakpad/Inputs/stack-cfi-parsing.yaml b/lldb/lit/SymbolFile/Breakpad/Inputs/stack-cfi-parsing.yaml new file mode 100644 index 00000000000..9f3a6316986 --- /dev/null +++ b/lldb/lit/SymbolFile/Breakpad/Inputs/stack-cfi-parsing.yaml @@ -0,0 +1,36 @@ +--- !minidump +Streams: + - Type: ThreadList + Threads: + - Thread Id: 0x00003E81 + Context: DEAD + Stack: + Start of Memory Range: 0x00007FFCEB34A000 + Content: DEAD + - Type: ModuleList + Modules: + - Base of Image: 0x0000000000400000 + Size of Image: 0x00001000 + Module Name: '/tmp/stack-cfi-parsing.out' + CodeView Record: 4C457042E35C283BC327C28762DB788BF5A4078BE2351448 + - Type: SystemInfo + Processor Arch: AMD64 + Processor Level: 6 + Processor Revision: 15876 + Number of Processors: 40 + Platform ID: Linux + CSD Version: 'Linux 3.13.0-91-generic' + CPU: + Vendor ID: GenuineIntel + Version Info: 0x00000000 + Feature Info: 0x00000000 + - Type: LinuxProcStatus + Text: | + Name: linux-x86_64 + State: t (tracing stop) + Tgid: 29917 + Ngid: 0 + Pid: 29917 + PPid: 29370 + +... diff --git a/lldb/lit/SymbolFile/Breakpad/stack-cfi-parsing.test b/lldb/lit/SymbolFile/Breakpad/stack-cfi-parsing.test new file mode 100644 index 00000000000..c8d9694172c --- /dev/null +++ b/lldb/lit/SymbolFile/Breakpad/stack-cfi-parsing.test @@ -0,0 +1,48 @@ +# RUN: yaml2obj %S/Inputs/stack-cfi-parsing.yaml > %t +# RUN: %lldb -c %t -o "target symbols add %S/Inputs/stack-cfi-parsing.syms" \ +# RUN: -s %s -b | FileCheck %s + +image show-unwind -n func0 +# CHECK-LABEL: image show-unwind -n func0 +# CHECK: Symbol file UnwindPlan: +# CHECK-NEXT: This UnwindPlan originally sourced from breakpad STACK CFI +# CHECK-NEXT: This UnwindPlan is sourced from the compiler: yes. +# CHECK-NEXT: This UnwindPlan is valid at all instruction locations: no. +# CHECK-NEXT: Address range of this UnwindPlan: [stack-cfi-parsing.out..module_image + 0-0x0000000000000002) +# CHECK-NEXT: row[0]: 0: CFA=DW_OP_breg7 +0 => rbp=DW_OP_breg7 +0 rip=DW_OP_pick 0x00 +# CHECK-NEXT: row[1]: 1: CFA=DW_OP_breg7 +0 => rbx=DW_OP_breg2 +0 rbp=DW_OP_breg0 +0 rip=DW_OP_pick 0x00 + +# The following plans are all (syntactically) invalid for various reasons. +# Processing those should not cause a crash. + +image show-unwind -n func2 +# CHECK-LABEL: image show-unwind -n func2 +# CHECK-NOT: Symbol file + +image show-unwind -n func3 +# CHECK-LABEL: image show-unwind -n func3 +# CHECK-NOT: Symbol file + +image show-unwind -n func4 +# CHECK-LABEL: image show-unwind -n func4 +# CHECK-NOT: Symbol file + +image show-unwind -n func5 +# CHECK-LABEL: image show-unwind -n func5 +# CHECK-NOT: Symbol file + +image show-unwind -n func6 +# CHECK-LABEL: image show-unwind -n func6 +# CHECK-NOT: Symbol file + +image show-unwind -n func7 +# CHECK-LABEL: image show-unwind -n func7 +# CHECK-NOT: Symbol file + +# Finally, try an unwind plan with just a single row +image show-unwind -n func9 +# CHECK-LABEL: image show-unwind -n func9 +# CHECK: Symbol file UnwindPlan: +# CHECK: Address range of this UnwindPlan: [stack-cfi-parsing.out..module_image + 9-0x000000000000000a) +# CHECK: row[0]: 0: CFA=DW_OP_breg6 +0 => rip=DW_OP_breg0 +0 + diff --git a/lldb/source/Plugins/SymbolFile/Breakpad/SymbolFileBreakpad.cpp b/lldb/source/Plugins/SymbolFile/Breakpad/SymbolFileBreakpad.cpp index 9057c2a8d3c..d4258274a38 100644 --- a/lldb/source/Plugins/SymbolFile/Breakpad/SymbolFileBreakpad.cpp +++ b/lldb/source/Plugins/SymbolFile/Breakpad/SymbolFileBreakpad.cpp @@ -15,9 +15,11 @@ #include "lldb/Host/FileSystem.h" #include "lldb/Symbol/CompileUnit.h" #include "lldb/Symbol/ObjectFile.h" +#include "lldb/Symbol/PostfixExpression.h" #include "lldb/Symbol/SymbolVendor.h" #include "lldb/Symbol/TypeMap.h" #include "lldb/Utility/Log.h" +#include "lldb/Utility/StreamString.h" #include "llvm/ADT/StringExtras.h" using namespace lldb; @@ -370,6 +372,155 @@ void SymbolFileBreakpad::AddSymbols(Symtab &symtab) { symtab.CalculateSymbolSizes(); } +static llvm::Optional<std::pair<llvm::StringRef, llvm::StringRef>> +GetRule(llvm::StringRef &unwind_rules) { + // Unwind rules are of the form + // register1: expression1 register2: expression2 ... + // We assume none of the tokens in expression<n> end with a colon. + + llvm::StringRef lhs, rest; + std::tie(lhs, rest) = getToken(unwind_rules); + if (!lhs.consume_back(":")) + return llvm::None; + + // Seek forward to the next register: expression pair + llvm::StringRef::size_type pos = rest.find(": "); + if (pos == llvm::StringRef::npos) { + // No pair found, this means the rest of the string is a single expression. + unwind_rules = llvm::StringRef(); + return std::make_pair(lhs, rest); + } + + // Go back one token to find the end of the current rule. + pos = rest.rfind(' ', pos); + if (pos == llvm::StringRef::npos) + return llvm::None; + + llvm::StringRef rhs = rest.take_front(pos); + unwind_rules = rest.drop_front(pos); + return std::make_pair(lhs, rhs); +} + +static const RegisterInfo * +ResolveRegister(const SymbolFile::RegisterInfoResolver &resolver, + llvm::StringRef name) { + if (name.consume_front("$")) + return resolver.ResolveName(name); + + return nullptr; +} + +static const RegisterInfo * +ResolveRegisterOrRA(const SymbolFile::RegisterInfoResolver &resolver, + llvm::StringRef name) { + if (name == ".ra") + return resolver.ResolveNumber(eRegisterKindGeneric, LLDB_REGNUM_GENERIC_PC); + return ResolveRegister(resolver, name); +} + +bool SymbolFileBreakpad::ParseUnwindRow(llvm::StringRef unwind_rules, + const RegisterInfoResolver &resolver, + UnwindPlan::Row &row) { + Log *log = GetLogIfAllCategoriesSet(LIBLLDB_LOG_SYMBOLS); + + llvm::BumpPtrAllocator node_alloc; + while (auto rule = GetRule(unwind_rules)) { + node_alloc.Reset(); + llvm::StringRef lhs = rule->first; + postfix::Node *rhs = postfix::Parse(rule->second, node_alloc); + if (!rhs) { + LLDB_LOG(log, "Could not parse `{0}` as unwind rhs.", rule->second); + return false; + } + + bool success = postfix::ResolveSymbols( + rhs, [&](postfix::SymbolNode &symbol) -> postfix::Node * { + llvm::StringRef name = symbol.GetName(); + if (name == ".cfa" && lhs != ".cfa") + return postfix::MakeNode<postfix::InitialValueNode>(node_alloc); + + if (const RegisterInfo *info = ResolveRegister(resolver, name)) { + return postfix::MakeNode<postfix::RegisterNode>( + node_alloc, info->kinds[eRegisterKindLLDB]); + } + return nullptr; + }); + + if (!success) { + LLDB_LOG(log, "Resolving symbols in `{0}` failed.", rule->second); + return false; + } + + ArchSpec arch = m_obj_file->GetArchitecture(); + StreamString dwarf(Stream::eBinary, arch.GetAddressByteSize(), + arch.GetByteOrder()); + ToDWARF(*rhs, dwarf); + uint8_t *saved = m_allocator.Allocate<uint8_t>(dwarf.GetSize()); + std::memcpy(saved, dwarf.GetData(), dwarf.GetSize()); + + if (lhs == ".cfa") { + row.GetCFAValue().SetIsDWARFExpression(saved, dwarf.GetSize()); + } else if (const RegisterInfo *info = ResolveRegisterOrRA(resolver, lhs)) { + UnwindPlan::Row::RegisterLocation loc; + loc.SetIsDWARFExpression(saved, dwarf.GetSize()); + row.SetRegisterInfo(info->kinds[eRegisterKindLLDB], loc); + } else + LLDB_LOG(log, "Invalid register `{0}` in unwind rule.", lhs); + } + if (unwind_rules.empty()) + return true; + + LLDB_LOG(log, "Could not parse `{0}` as an unwind rule.", unwind_rules); + return false; +} + +UnwindPlanSP +SymbolFileBreakpad::GetUnwindPlan(const Address &address, + const RegisterInfoResolver &resolver) { + ParseUnwindData(); + const UnwindMap::Entry *entry = + m_unwind_data->FindEntryThatContains(address.GetFileAddress()); + if (!entry) + return nullptr; + + addr_t base = GetBaseFileAddress(); + if (base == LLDB_INVALID_ADDRESS) + return nullptr; + + LineIterator It(*m_obj_file, Record::StackCFI, entry->data), End(*m_obj_file); + llvm::Optional<StackCFIRecord> init_record = StackCFIRecord::parse(*It); + assert(init_record.hasValue()); + assert(init_record->Size.hasValue()); + + auto plan_sp = std::make_shared<UnwindPlan>(lldb::eRegisterKindLLDB); + plan_sp->SetSourceName("breakpad STACK CFI"); + plan_sp->SetUnwindPlanValidAtAllInstructions(eLazyBoolNo); + plan_sp->SetSourcedFromCompiler(eLazyBoolYes); + plan_sp->SetPlanValidAddressRange( + AddressRange(base + init_record->Address, *init_record->Size, + m_obj_file->GetModule()->GetSectionList())); + + auto row_sp = std::make_shared<UnwindPlan::Row>(); + row_sp->SetOffset(0); + if (!ParseUnwindRow(init_record->UnwindRules, resolver, *row_sp)) + return nullptr; + plan_sp->AppendRow(row_sp); + for (++It; It != End; ++It) { + llvm::Optional<StackCFIRecord> record = StackCFIRecord::parse(*It); + if (!record.hasValue()) + return nullptr; + if (record->Size.hasValue()) + break; + + row_sp = std::make_shared<UnwindPlan::Row>(*row_sp); + row_sp->SetOffset(record->Address - init_record->Address); + if (!ParseUnwindRow(record->UnwindRules, resolver, *row_sp)) + return nullptr; + plan_sp->AppendRow(row_sp); + } + return plan_sp; +} + SymbolVendor &SymbolFileBreakpad::GetSymbolVendor() { return *m_obj_file->GetModule()->GetSymbolVendor(); } @@ -476,3 +627,27 @@ void SymbolFileBreakpad::ParseLineTableAndSupportFiles(CompileUnit &cu, finish_sequence(); data.support_files = map.translate(cu, *m_files); } + +void SymbolFileBreakpad::ParseUnwindData() { + if (m_unwind_data) + return; + + m_unwind_data.emplace(); + Log *log = GetLogIfAllCategoriesSet(LIBLLDB_LOG_SYMBOLS); + addr_t base = GetBaseFileAddress(); + if (base == LLDB_INVALID_ADDRESS) { + LLDB_LOG(log, "SymbolFile parsing failed: Unable to fetch the base address " + "of object file."); + } + + for (LineIterator It(*m_obj_file, Record::StackCFI), End(*m_obj_file); + It != End; ++It) { + if (auto record = StackCFIRecord::parse(*It)) { + if (record->Size) + m_unwind_data->Append(UnwindMap::Entry( + base + record->Address, *record->Size, It.GetBookmark())); + } else + LLDB_LOG(log, "Failed to parse: {0}. Skipping record.", *It); + } + m_unwind_data->Sort(); +} diff --git a/lldb/source/Plugins/SymbolFile/Breakpad/SymbolFileBreakpad.h b/lldb/source/Plugins/SymbolFile/Breakpad/SymbolFileBreakpad.h index 2760a5a573e..8a0b7645fd0 100644 --- a/lldb/source/Plugins/SymbolFile/Breakpad/SymbolFileBreakpad.h +++ b/lldb/source/Plugins/SymbolFile/Breakpad/SymbolFileBreakpad.h @@ -13,6 +13,7 @@ #include "lldb/Core/FileSpecList.h" #include "lldb/Symbol/LineTable.h" #include "lldb/Symbol/SymbolFile.h" +#include "lldb/Symbol/UnwindPlan.h" namespace lldb_private { @@ -133,6 +134,10 @@ public: void AddSymbols(Symtab &symtab) override; + lldb::UnwindPlanSP + GetUnwindPlan(const Address &address, + const RegisterInfoResolver &resolver) override; + ConstString GetPluginName() override { return GetPluginNameStatic(); } uint32_t GetPluginVersion() override { return 1; } @@ -144,6 +149,11 @@ private: struct Bookmark { uint32_t section; size_t offset; + + friend bool operator<(const Bookmark &lhs, const Bookmark &rhs) { + return std::tie(lhs.section, lhs.offset) < + std::tie(rhs.section, rhs.offset); + } }; // At iterator class for simplifying algorithms reading data from the breakpad @@ -177,8 +187,7 @@ private: return *this; } friend bool operator<(const CompUnitData &lhs, const CompUnitData &rhs) { - return std::tie(lhs.bookmark.section, lhs.bookmark.offset) < - std::tie(rhs.bookmark.section, rhs.bookmark.offset); + return lhs.bookmark < rhs.bookmark; } Bookmark bookmark; @@ -192,11 +201,19 @@ private: void ParseFileRecords(); void ParseCUData(); void ParseLineTableAndSupportFiles(CompileUnit &cu, CompUnitData &data); + void ParseUnwindData(); + bool ParseUnwindRow(llvm::StringRef unwind_rules, + const RegisterInfoResolver &resolver, + UnwindPlan::Row &row); using CompUnitMap = RangeDataVector<lldb::addr_t, lldb::addr_t, CompUnitData>; llvm::Optional<std::vector<FileSpec>> m_files; llvm::Optional<CompUnitMap> m_cu_data; + + using UnwindMap = RangeDataVector<lldb::addr_t, lldb::addr_t, Bookmark>; + llvm::Optional<UnwindMap> m_unwind_data; + llvm::BumpPtrAllocator m_allocator; }; } // namespace breakpad |
